Non-specific primer extension prior to reaction initiation in thermocycling DNA amplification reactions such as polymerase chain reaction (PCR), or isothermal DNA amplification reactions such as loop-mediated isothermal amplification (LAMP) may inhibit specific product formation, and lead to non-specific amplification and reaction irreproducibility. It is, therefore, desirable to block the activity of the polymerase, and hence primer extension, prior to reaction initiation. This has been achieved using antibodies (Kellogg, et al., Biotechniques, 16(6):1134-7 (1994)), affybodies (Affibody AB, Stockholm, Sweden), aptamers (Dang, et al., Journal of Molecular Biology, 264(2):268-78 (1996)), and chemical modification of the polymerase (U.S. Pat. No. 6,183,998). Although each of these techniques can be effective, they each have unique limitations. For example, preparation of antibodies requires use of animal systems, affybodies and aptamers require screening libraries of molecular variants, and chemical modifications require extra heat incubation steps to reverse the inactivating modification. It would be desirable to have a generalizable approach to rapidly and effectively create hot-start inhibitors targeted towards DNA polymerases.